The invention relates to a process for preparing a siliceous inorganic material especially in the form of fibers particularly suitable for obtaining organomineral copolymers, and more particularly to be used as a filler for strengthening polymers and elastomers. It concerns also siliceous materials as obtained in this process and their applications for the achievement of organomineral composites, chiefly as strengthening fillers for polymers or elastomers.
The main object of the invention is to make possible the grafting of organic radicals on a mineral siliceous framework, and more particularly on the two-dimensional siliceous framework of the phyllosilicates.
This last word refers to minerals having in their structure at least a tetraedral layer of silica and oxygen and at least an octaedral layer that can be eliminated by acid hdyrolysis and containing particularly magnesium, aluminum and/or iron. Within the scope of the invention, these minerals are preferably fibrous, such as chrysotile or optionnaly sepiolite, or lamellar as mica, hydromica and vermiculite. All these minerals are cited as particularly common but these examples are not intended to be restrictive.
In fact, the use of phyllosilicates or products derived from phyllosilicates as strengthening fillers in polymers or elastomers is already well known. The grafting of polymerizable organic radicals on phyllosilicates by means of silanes has been already proposed.
With regard to such known processes, the invention aims at making the preparation of such products easier and at decreasing their cost price, in particular by avoiding the use of silanes.